length(x)=5, assigning to a function to to set the length of an object? really ?

“1” based array index (FORTRAN, anyone?)

complete textual orientation (OK, not a problem for an emacs user)

Having to think about the size of objects being read in (echos of the days before virtual memory)

On the other hand, I was able to generate a heatmap in 3 lines of code (thanks to Bronwyn Woods for the pointer). I spent hours messing around with Python and JavaScript versions, but the R version Just Worked. Three lines. Amazing.